From US 2010/0019518 A1 a crashbox with main portion and anchoring portion is known, wherein the anchoring portion is slightly tapered relative to the main portion, so that a shoulder which connects the two portions, supports itself on the front edge of the side member in the event of a collision. In order to prevent that the shoulder slides off the front edge of the side member and the main portion of the crashbox also enters the side member, the latter is stiffened through a support body. This support body is substantially formed through a plate extending in the main portion at a small distance from the shoulder and filling out the cross section of the crashbox as well as a plurality of flanges angled-off the plate and jointly screwed to the walls of the anchoring portion on insides of the side member. In that these flanges cross the plane of the shoulder and are fixed on a side of this plane through the plate and on the other one through the screwing to the side member, they can prevent an inwardly directed deformation of the main portion of the crashbox.
The anchoring portion of this conventional crashbox in cross section transversely to the longitudinal axis of the crashbox substantially has the shape of a rectangle with continuous walls and rounded-off corners. The cross section of the anchoring portion has to be very precisely matched to the cross section of the side member since an oversize of the anchoring portion prevents inserting the side member and an undersize results in that either the shoulder formed between main and anchoring portion can only support itself on the side member on a part of its length and of two walls of the anchoring portion located opposite each other only one can be screwed to an inner surface of the side member through frictional connection or that the side member is deformed during the attempt of offsetting the undersize of the anchoring portion.
In order to solve this problem, a crashbox was developed, wherein an anchoring portion comprises two elements that are U-shaped or channel-shaped in cross section, which are interconnected only via the main portion. This produces the possibility of spreading the walls of the anchoring portion located opposite each other apart when fixing it to the side member by screwing so that both walls of the anchoring portion thus pressing both walls of the anchoring portion tightly against the insides of the side member without bending the latter in the process.
Tests have shown that the walls of the anchoring portion of this crashbox during a collision have a tendency of spreading apart scissor-like and in the process, expand the side member distant from its open end. Like any repair on the side member, rectifying such an expansion, provided it is at all economical, is labor-intensive and expensive.
Accordingly, it is desirable to provide a motor vehicle with an improved crashbox, wherein the tendency of a side member to be negatively affected during a collision is further reduced. In addition, other objects, desirable features and characteristics will become apparent from the subsequent summary and detailed description, and the appended claims, taken in conjunction with the accompanying drawings and this background.